Well, that didn't take very long. Just two days after NUI Group's AlexP announced that he had managed to access Kinect's functionality via PC, a lone hacker by the name of Hector Martin has managed the same thing. What's more, Martin has openly released his code to the public. NUI Group, for what it's worth, is busy creating a Kinect SDK and will release it once the group receives a certain level of monetary donations.
See Martin's results after the break. For those brave enough (and good enough with code), Martin's Kinect driver can be downloaded here. Keep in mind that the driver does little more than display what the Kinect "sees" at this point, specifically the RGB and depth-sensing camera feeds. Without software to utilize it, the driver is essentially just a fun party trick ... for now.